*{margin:0;padding:0;box-sizing:border-box}
html,body{width:100%;height:100%;overflow:hidden;touch-action:none;user-select:none}
canvas{display:block;position:absolute;top:0;left:0}
#rotate{display:none;position:fixed;inset:0;background:#1a3a6e;color:#fff;
  font-family:'Nunito',sans-serif;font-size:1.4rem;font-weight:700;
  flex-direction:column;align-items:center;justify-content:center;gap:16px;z-index:999}
#rotate span{font-size:3.5rem;animation:tilt 2s ease-in-out infinite}
@keyframes tilt{0%,100%{transform:rotate(0)}50%{transform:rotate(90deg)}}
@media(orientation:portrait){#rotate{display:flex}}
@media(orientation:landscape){#rotate{display:none}}